This invention relates generally to the field of surgical instruments and methods. More particularly, it relates to an apparatus and method for suture ligation of blood vessels and other bodily ducts, using a laparoscopic access site.
Laparoscopy has become increasingly popular as a technique of minimally invasive surgery because of its significant advantages over conventional surgical techniques: reduced surgical trauma and scarring, substantially less pain and discomfort, significantly decreased risks of infection, and shortened recuperation times (and thus shorter, less expensive hospital stays). Thus, laparoscopy has been used in such procedures as cholecystectomy, hysterectomy, bowel resection, and hernia repair.
In laparoscopy, all of the steps of a surgical procedure (such as dissection, cutting, suturing, and ligating) are performed by means of elongated instruments that are inserted into the abdominal cavity via trocars that, in turn, are inserted through small, "minimally invasive" incisions or punctures.
One of the more difficult surgical skills to acquire is that of laparoscopic knot-tying or ligation of vessels and tissue pedicles and the like. Ligation of such structures during laparoscopy requires the passing of sutures and the tying of knots remotely, using elongated forceps, under videoscopic observation. Several devices have come into use to facilitate laparoscopic ligation, but these have either required the use of clips that may be prone to dislodgement, or the use of preformed suture loops that necessitate the cutting of the vessel prior to tightening the knot, so that the loop may be placed around a free end of the vessel, (which may be disadvantageous in some procedures). Furthermore, some prior art devices may require the surgeon to learn complicated new knots, or they may require additional access sites to complete or tighten the knot.
While there have been a number of suture-tying or ligation devices developed in the prior art, none of these is particularly well-suited to laparoscopic procedures.
For example, Soviet Union Patent No. 549,146 discloses a device for applying ligatures to a blood vessel or the like, comprising an elongate, hollow body having a conical head, and a hook extending from the body so that its terminus is spaced from and opposed to the head. The hook has a grooved aperture near its terminus. A length of ligature is wrapped around the body near the head in one or more loops, and includes a segment that is carried in the groove across the aperture. A retractable rod is carried in the body, the rod having a finger at one end that is insertable through the head and into the aperture. In use, the hook is guided under the vessel to be ligated, and the rod is inserted through the aperture so that the finger grasps the ligature. The rod is then retracted into the head, pulling the ligature with it. The loops of the ligature are then manually slid off the head and over the portion of the ligature pulled toward the head by the rod, and then manually tightened to form a knot around the vessel. This need for the surgeon to reach into the surgical sight with his or her fingers to manipulate and tighten the ligature loops manually thus necessitates an enlarged surgical opening, thereby making a device of this type unsuitable for minimally invasive surgery, such as laparoscopy.
U.S. Pat. No. 5,059,201--Asnis discloses a tool that can be used for ligating a vessel during a laparoscopic procedure. The device includes an elongate outer tube with a bracket on the end. The outer tube carries an axially-movable inner tube, which, in turn, contains an axially-movable shaft with a notch on its end. One end of a suture is clamped to the handle end of the device and is threaded across the bracket. The bracket is placed under a vessel, and the inner tube is extended to capture the vessel. The shaft is then extended through a hole in the bracket to capture the suture in the notch of the shaft. The shaft and the inner tube are then withdrawn into the outer tube to draw the suture around the vessel. A slip knot can then be formed around the vessel, but the knot must be tightened with a separate implement comprising a shaft with a ring at one end. In other words, the Asnis device lacks self-contained means for manipulating and tightening the knot, requiring a separate tool for this task.
U.S. Pat. No. 2,455,833--Trombetta and U.S. Pat. No. 3,985,138--Jarvik disclose ligating devices having clamping jaws for grasping a vessel to be ligated while a suture is tied around the vessel. While these devices (and especially the Jarvik device) may be adapted for use through a trocar, both devices require severing and clamping of the vessel prior to the application of the ligatures, and thus may be disadvantageous where clamping is sought to be avoided or minimized.
Other devices for applying ligatures are disclosed in U.S. Pat. No. 1,400,653--Barbour; U.S. Pat. No. 1,545,682--Nelson; U.S. Pat. No. 3,040,747--Wood; and British Patent No. 479,719--Webb et al. The devices are typically forceps-like implements that are not adapted for insertion and use through a trocar, and that may require clamping of the vessel and/or manual manipulation and tightening of the ligature knot.
Thus, there has been an as-yet unfulfilled need for a ligature tying device that is suitable for use through a trocar for laparoscopic procedures, that includes self-contained means for manipulating and tightening the ligature knot through the trocar without the need for manual manipulation and tightening, and that do not require clamping of the vessel. Furthermore, it would be advantageous to provide such a device that is also simple to manufacture and to use, and that does not require the use of new, complex suture knots. It would be further advantageous to provide a device of this nature that can be made in a disposable or single use embodiment.